Class PacketOutputStream

java.lang.Object

java.io.OutputStream

org.refcodes.serial.PacketOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable, BlockSizeAccessor, PacketSizeAccessor, EndianessAccessor, PacketLengthWidthAccessor, PacketMagicBytesAccessor, PacketSegmentPackagerAccessor, SequenceNumberAccessor, SequenceNumberConcatenateModeAccessor, SequenceNumberInitValueAccessor, SequenceNumberWidthAccessor

Direct Known Subclasses:

StopAndWaitPacketOutputStream

public class PacketOutputStream
extends OutputStream
implements PacketLengthWidthAccessor, PacketSizeAccessor, EndianessAccessor, BlockSizeAccessor, SequenceNumberInitValueAccessor, SequenceNumberConcatenateModeAccessor, SequenceNumberAccessor, SequenceNumberWidthAccessor, PacketSegmentPackagerAccessor, PacketMagicBytesAccessor

The PacketOutputStream wraps an OutputStream and chunks any data to be written into packets with a sequence number, a block of data and a CRC checksum. An according StopAndWaitPacketInputStream then reverts the packetised data stream while performing CRC checksum validation as well as sequence number validation. ATTENTION: In order to send the last packet (block of data), call flush() so that it is transmitted even if the block is not completely filled with bytes.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PacketOutputStream.Builder	Builder to build StopAndWaitPacketInputStream instances.

Nested classes/interfaces inherited from interface BlockSizeAccessor

BlockSizeAccessor.BlockSizeBuilder<B>, BlockSizeAccessor.BlockSizeMutator, BlockSizeAccessor.BlockSizeProperty

Nested classes/interfaces inherited from interface EndianessAccessor

EndianessAccessor.EndianessBuilder<B>, EndianessAccessor.EndianessMutator, EndianessAccessor.EndianessProperty

Nested classes/interfaces inherited from interface PacketLengthWidthAccessor

PacketLengthWidthAccessor.PacketLengthWidthBuilder<B>, PacketLengthWidthAccessor.PacketLengthWidthMutator, PacketLengthWidthAccessor.PacketLengthWidthProperty

Nested classes/interfaces inherited from interface PacketMagicBytesAccessor

PacketMagicBytesAccessor.PacketMagicBytesBuilder<B>, PacketMagicBytesAccessor.PacketMagicBytesMutator, PacketMagicBytesAccessor.PacketMagicBytesProperty

Nested classes/interfaces inherited from interface PacketSegmentPackagerAccessor

PacketSegmentPackagerAccessor.PacketSegmentPackagerBuilder<B>, PacketSegmentPackagerAccessor.PacketSegmentPackagerMutator, PacketSegmentPackagerAccessor.PacketSegmentPackagerProperty

Nested classes/interfaces inherited from interface PacketSizeAccessor

PacketSizeAccessor.PacketSizeBuilder<B>, PacketSizeAccessor.PacketSizeMutator, PacketSizeAccessor.PacketSizeProperty

Nested classes/interfaces inherited from interface SequenceNumberAccessor

SequenceNumberAccessor.SequenceNumberBuilder<B>, SequenceNumberAccessor.SequenceNumberMutator, SequenceNumberAccessor.SequenceNumberProperty

Nested classes/interfaces inherited from interface SequenceNumberConcatenateModeAccessor

SequenceNumberConcatenateModeAccessor.SequenceNumberConcatenateModeBuilder<B>, SequenceNumberConcatenateModeAccessor.SequenceNumberConcatenateModeMutator, SequenceNumberConcatenateModeAccessor.SequenceNumberConcatenateModeProperty

Nested classes/interfaces inherited from interface SequenceNumberInitValueAccessor

SequenceNumberInitValueAccessor.SequenceNumberInitValueBuilder<B>, SequenceNumberInitValueAccessor.SequenceNumberInitValueMutator, SequenceNumberInitValueAccessor.SequenceNumberInitValueProperty

Nested classes/interfaces inherited from interface SequenceNumberWidthAccessor

SequenceNumberWidthAccessor.SequenceNumberWidthBuilder<B>, SequenceNumberWidthAccessor.SequenceNumberWidthMutator, SequenceNumberWidthAccessor.SequenceNumberWidthProperty

Field Summary

Fields

Modifier and Type	Field	Description
protected AllocSectionDecoratorSegment<SequenceSection>	_allocSegment
protected int	_blockOffset
protected Sequence	_blockSequence
protected BoundedSequenceDecorator	_boundedSequence
protected Endianess	_endianess
protected OutputStream	_outputStream
protected Segment	_packetSegment
protected int	_sequenceNumber
protected NumberSegment	_sequenceNumberSegment
protected int	_sequenceNumberWidth

Constructor Summary

Constructors

Constructor	Description
PacketOutputStream(OutputStream aOutputStream, int aBlockSize, int aPacketLengthWidth, byte[] aPacketMagicBytes, int aSequenceNumberInitValue, int aSequenceNumberWidth, ConcatenateMode aSequenceNumberConcatenateMode, SegmentPackager aPacketSegmentPackager, Endianess aEndianess)	Constructs an according PacketOutputStream instance wrapping the given OutputStream.
PacketOutputStream(OutputStream aOutputStream, TransmissionMetrics aTransmissionMetrics)	Constructs an according PacketOutputStream instance wrapping the given OutputStream.

Method Summary

Modifier and Type	Method	Description
static PacketOutputStream.Builder	builder()	Creates builder to build PacketOutputStream.
void	close()
protected void	doTransmitPacket()	Do transmit packet.
void	flush()	In case a packet is not complete (e.g. it's block's data did filled till the getBlockSize() length), then the package is sent with it's block data "as is" (a last block's data might get filled up with zeros).
int	getBlockSize()
Endianess	getEndianess()
int	getPacketLengthWidth()	Retrieves the packet length width (in bytes) from the packet length width (in bytes) property.
byte[]	getPacketMagicBytes()	Retrieves the magic bytes from the packet magic bytes property.
SegmentPackager	getPacketSegmentPackager()	Retrieves the SegmentPackager from the packet SegmentPackager property.
int	getPacketSize()
int	getSequenceNumber()	Retrieves the sequence number from the sequence number property.
ConcatenateMode	getSequenceNumberConcatenateMode()	Retrieves the ConcatenateMode from the sequence number ConcatenateMode property.
int	getSequenceNumberInitValue()	Retrieves the sequence number initial value from the sequence number initial value property.
int	getSequenceNumberWidth()	Retrieves the sequence number width (in bytes) from the sequence number width (in bytes) property.
void	write(int b)

Methods inherited from class OutputStream

nullOutputStream, write, write

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

_blockOffset

protected int _blockOffset

_blockSequence

protected Sequence _blockSequence

_endianess

protected Endianess _endianess

_outputStream

protected OutputStream _outputStream

_packetSegment

protected Segment _packetSegment

_sequenceNumber

protected int _sequenceNumber

_sequenceNumberSegment

protected NumberSegment _sequenceNumberSegment

_sequenceNumberWidth

protected int _sequenceNumberWidth

_allocSegment

protected AllocSectionDecoratorSegment<SequenceSection> _allocSegment

_boundedSequence

protected BoundedSequenceDecorator _boundedSequence

Constructor Details

PacketOutputStream

public PacketOutputStream(OutputStream aOutputStream,
 TransmissionMetrics aTransmissionMetrics)

Constructs an according PacketOutputStream instance wrapping the given OutputStream. The configuration attributes are taken from the TransmissionMetrics configuration object, though only those attributes are supported which are also supported by the other constructors!

Parameters:

aOutputStream - The OutputStream to be wrapped.

aTransmissionMetrics - The TransmissionMetrics to be used for configuring this instance.

PacketOutputStream

public PacketOutputStream(OutputStream aOutputStream,
 int aBlockSize,
 int aPacketLengthWidth,
 byte[] aPacketMagicBytes,
 int aSequenceNumberInitValue,
 int aSequenceNumberWidth,
 ConcatenateMode aSequenceNumberConcatenateMode,
 SegmentPackager aPacketSegmentPackager,
 Endianess aEndianess)

Constructs an according PacketOutputStream instance wrapping the given OutputStream.

Parameters:

aOutputStream - The OutputStream to be wrapped.

aBlockSize - The block size of a data block for each packet.

aPacketLengthWidth - The width (bytes) for declaring the (max) length of a package.

aPacketMagicBytes - The magic bytes identifying a packet and distinguishing a packet from a last package.

aSequenceNumberInitValue - The initial sequence number from where to start counting the blocks.

aSequenceNumberWidth - The width (in bytes) to be used for sequence number values.

aSequenceNumberConcatenateMode - The mode of concatenation to use when creating a Sequence from this Transmission and the decorated Transmission.

aPacketSegmentPackager - An (optional) SegmentPackager used to modify a packet's data e.g. with a CRC checksum.

aEndianess - The Endianess to use for integer (double) numbers and the like.

Method Details

builder

public static PacketOutputStream.Builder builder()

Creates builder to build PacketOutputStream.

Returns:

created builder

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

In case a packet is not complete (e.g. it's block's data did filled till the getBlockSize() length), then the package is sent with it's block data "as is" (a last block's data might get filled up with zeros).

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

getBlockSize

public int getBlockSize()

Specified by:

getBlockSize in interface BlockSizeAccessor

getEndianess

public Endianess getEndianess()

Specified by:

getEndianess in interface EndianessAccessor

getPacketMagicBytes

public byte[] getPacketMagicBytes()

Retrieves the magic bytes from the packet magic bytes property.

Specified by:

getPacketMagicBytes in interface PacketMagicBytesAccessor

Returns:

The magic bytes stored by the packet magic bytes property.

getPacketSegmentPackager

public SegmentPackager getPacketSegmentPackager()

Retrieves the SegmentPackager from the packet SegmentPackager property.

Specified by:

getPacketSegmentPackager in interface PacketSegmentPackagerAccessor

Returns:

The SegmentPackager stored by the packet SegmentPackager property.

getPacketSize

public int getPacketSize()

Specified by:

getPacketSize in interface PacketSizeAccessor

getSequenceNumber

public int getSequenceNumber()

Retrieves the sequence number from the sequence number property.

Specified by:

getSequenceNumber in interface SequenceNumberAccessor

Returns:

The sequence number stored by the sequence number property.

getSequenceNumberConcatenateMode

public ConcatenateMode getSequenceNumberConcatenateMode()

Retrieves the ConcatenateMode from the sequence number ConcatenateMode property.

Specified by:

getSequenceNumberConcatenateMode in interface SequenceNumberConcatenateModeAccessor

Returns:

The ConcatenateMode stored by the sequence number ConcatenateMode property.

getSequenceNumberInitValue

public int getSequenceNumberInitValue()

Retrieves the sequence number initial value from the sequence number initial value property.

Specified by:

getSequenceNumberInitValue in interface SequenceNumberInitValueAccessor

Returns:

The sequence number initial value stored by the sequence number initial value property.

getSequenceNumberWidth

public int getSequenceNumberWidth()

Retrieves the sequence number width (in bytes) from the sequence number width (in bytes) property.

Specified by:

getSequenceNumberWidth in interface SequenceNumberWidthAccessor

Returns:

The sequence number width (in bytes) stored by the sequence number width (in bytes) property.

getPacketLengthWidth

public int getPacketLengthWidth()

Retrieves the packet length width (in bytes) from the packet length width (in bytes) property.

Specified by:

getPacketLengthWidth in interface PacketLengthWidthAccessor

Returns:

The packet length width (in bytes) stored by the packet length width (in bytes) property.

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

doTransmitPacket

protected void doTransmitPacket()
                         throws IOException

Do transmit packet.

Throws:

IOException - Signals that an I/O exception has occurred.